this is why i suggested a trusted list !
it could be a sticky at the top of every section,this way you put up who you have had a good deal with 100%,then at least members can have a look if the person they intend on dealing with ,is on it!
then if so they can make there own mind up,if they would like to deal with them.
but F2F is the way to go if you are dealing/selling on any forum, especially with your hard earn't cash!!!